For the first time, a Gram-positive microorganism capable of degrading 4-hydroxypyridine was isolated by enrichment techniques from soil. The isolate IN13 utilizes also 2-hydroxypyridine as a sole carbon, nitrogen and energy source. During the degradation of 2-hydroxypyridine a soluble blue pigment was accumulated in the culture. The 16S rRNA-based phylogeny analysis has indicated that the IN13 isolate belongs to the genus Arthrobacter and with Arthrobacter sp. A4Z24, Arthrobacter sp. A1-1, and several uncultured strains forms a separate group. The biodegradation of 4-hydroxypyridine and 2-hydroxypyridine was investigated. Biodegradation studies with washed cells confirmed 4-hydroxypyridine and 2-hydroxypyridine consumption. IN13 growing in a medium with 2-hydroxypyridine tends to lose its 4-hydroxypyridine degrading activity at a significant rate.